A luminaria, in general terms, refers to a light source or a small lantern. The luminaria is most commonly a candle in a paper lamp shade, used as a holiday lantern. In some countries, including the United States, the luminaria is made from brown paper bags, weighted down with some form of ballast (e.g., sand, gravel, water, etc.) and illuminated from within by a light source (e.g., a candle). Luminarias have been used traditionally since the 16th century as a holiday lantern, as a means to denote trails for people traveling to a church or other gatherings during the holiday season. Luminarias are typically arranged in rows to create elaborate displays.
The earliest luminarias were made by using small bonfires along, for example, a trail to a church. During the 1700s, traditional Christmas luminarias were made using a candle set in sand within a paper bag. In some places, luminarias are made using votive candles placed within paper bags, weighted down using sand in the paper bags. Modern luminarias use LED lights or electric bulbs to provide the light source. Although luminarias started out as a holiday tradition, it is currently used in a plethora or festive occasions and is not restricted to specific religious events.
Luminarias are most frequently used in a pattern or array, where several individual luminarias are placed in, for example, a linear array along sidewalks, driveways, park trails, etc. Apart from its use for decorative and festive purposes, luminarias serve as navigation leads to guide people in poorly-lit areas. For example, luminarias are used in park trails to lead people to the location of, for example, a midnight concert.
There are several disadvantages with the luminarias used as discussed above, some of which are detailed here. First, when paper bags are used, they are prone to collecting moisture and breaking out or disintegrating, causing the ballast used inside to be strewn around and creating unwanted debris.
Second, when using ballast materials to weigh down the luminarias, a person is often unsure how much ballast material to fill inside the luminaria's container. This causes a person, in some instances, to overuse ballast causing the luminaria to become heavier and cumbersome to carry around, and also causes the outer container to tear away or wear out due to the additional weight. A person may also use too little ballast, failing to provide the luminaria with sufficient support to weigh it down.
Third, using water or other liquid ballasts to weigh down the luminaria causes a different set of problems. Use of water or liquids requires a closed container to be used within the luminaria to hold the ballast. When used in colder climates, the water freezes, causing its surface area to expand, leading to the container to crack or break.
Fourth, using candles within paper bags presents a substantial fire hazard. Even with ballast, the paper bags are prone to tipping over, causing the open flame from the candle to set the paper bag on fire. Even with a slight windy condition, the panels of the paper bag are prone to being blown toward the open flame, causing the paper bag to be set on fire.
Fifth, electric luminarias using string lights use the 120V alternating current, and present several hazards when used in out door environments. The electric luminaria has to be well insulated to prevent moisture from accumulating and creating the risk of electrocution. The use of the 120V AC power in outdoor environments also creates a fire hazard. The use of the insulators and other protective measures dramatically increases the cost of each luminaria, making it less attractive for use in extensive displays.
Sixth, some luminarias are rooted to the ground using nails or spikes instead of using ballast materials. However, as luminarias leave the traditional landscape and begin to be used on paved surfaces, nails or spikes are unusable to root the luminarias firmly.